Oxygen diluter device

ABSTRACT

An improved device for controlling oxygen concentration delivered to an oxygen mask comprises a nozzle portion disposed at one end for attaching an oxygen delivery tube, a hollow gas delivery portion at the opposite end for directing gas to an oxygen mask and a tunnel portion disposed between the nozzle and gas delivery portion having support bars extending between the nozzle and delivery portions and a plurality of spaced arcuate ribs secured along the bars between which ribs are defined a plurality of air entrainment ports through which atmospheric air is drawn for diluting a stream of oxygen passing along the tunnel. Air restriction closure members are secured between the ribs selectively closing one or more of the ports for metering air entrainment and oxygen concentration delivered to the mask.

Diedrich et a1.

[451 Feb. 26, 1974 OXYGEN DILUTER DEVICE [75] Inventors: Donald F.Diedrich, Temecula; John H. Price, La Jolla, both of Calif.

[73] Assignee: Hudson Oxygen Therapy Sales Company, Temecula, Calif.

22 Filed: June 26,1972

21 Appl.No.: 266,226

[52] US. Cl. 137/604, 128/209 [51] lint. Cl. Fl6k 15/00 [58] Field ofSearch... 128/209, 210, 197, 205, 185, 128/194, 145 R, l45.5-145.8;137/604;

Primary ExaminerRichard A. Gaudet Assistant Examiner-Lee S. CohenAttorney, Agent, or Firm-Jerry R. Seiler [57] ABSTRACT An improveddevice for controlling oxygen concentration delivered to an oxygen maskcomprises a nozzle portion disposed at one end for attaching an oxygendelivery tube, a hollow gas delivery portion at the opposite end fordirecting gas to an oxygen mask and a tunnel portion disposed betweenthe nozzle and gas delivery portion having support bars extendingbetween the nozzle and delivery portions and a plurality of spacedarcuate ribs secured along the bars between which ribs are defined aplurality of air entrainment ports through which atmospheric air isdrawn for diluting a stream of oxygen passing along the tunnel. Airrestriction closure members are secured between the ribs selectivelyclosing one or more of the ports for metering air entrainment and oxygenconcentration delivered to the mask.

4 Claims, 10 Drawing Figures PAIENTEUFEBZBiH'M "sum 1 0r 3 FIGURE!FIGURE 5 FIGURE 2 FIGURE 4 PATENTEUFEBZS'QY" 3,794,072

sum .2 or 3 FIGURE 5 FIGURE 6 4 FIGURE 7 FiGURE 9 PAIENTEDFEBZWH$194,072

' SHEU 3 (IF 3 FIGURE 10 OXYGEN DILUlllElR DEVICE BACKGROUND OF THEINVENTION A number of devices for diluting the concentration of oxygensupplied to patients receiving inhalation therapy have been proposed.Such prior art devices usually include a nozzle for securing an oxygensupply tube and an enlarged apertured venturi tunnel portion into whichthe oxygen is directed from the nozzle. Normally, large bore tubing isattached between the apertured venturi portion and an oxygen masksecured on a patient for delivery of the oxygen enriched gas.

As the high flow of oxygen passesfrom the nozzle into the enlargedtunnel, a partial vacuum in the vicinity of the oxygen stream is createdwhich stream becomes entrained and diluted with room air drawn throughthe orifices. The problem with such prior art diluter devices-is thatthe orifices communicating between the venturi chamber and roomatmosphere supply only a single oxygen dilution ratio at a specifiedoxygen flow rate. However, for different patients, different dilutionsmay be desired to provide different oxygen concentrations, for example,24, 28, 35 and 40 percent with each of these concentrations requiringseparate units having different sized orifices in order to achievedifferent dilutions. In other words, since one unit will provide only asingle oxygen concentration, to have a range of diluters on hand, fourseparate units must be purchased, obviously increasing costs and storageand handling requirements. Moreover, even though the diluters areintended as disposable units to avoid contamination from patient topatient, where a single patient requires differing oxygenconcentrations, it will be necessary to provide different individualdiluters.

SUMMARY OF THE INVENTION It is to the elimination of the above noteddisadvantages that the present invention is directed. The deviceincorporates an improved dilution chamber which can be altered to givethe full range of usual oxygen concentrations required for mostpatients. The device, intended to be used in combination with an oxygenmask includes a nozzle portion for securing an oxygen delivery tube.Extending from one end of the nozzle, opposite the end for attaching theoxygen delivery tube, is a gas metering tunnel portion comprising aplurality of spaced arcuate ribs between which ribs are defined aplurality of dilution ports. The ribs are attached to and suspendedbetween a pair of oppositely disposed bars or rods which bars areattached between the nozzle portion and a hollow gas delivery portionthe latter which directs the diluted oxygen to an oxygen mask. Thedevice also includes a plurality of closure members for selectivelyclosing one or more of the air entrainment ports as desired for varyingthe amount of entrained atmospheric air entering the mixing chamber andconcomitantly the oxygen concentration delivered to the patient. Theclosure members may be inserted or removed as desired so that thevarying oxygen concentrations may be achieved with a single devicewithout the requirement of utilizing separate diluter devices to achievediffering oxygen concentrations as has been necessitated by prior artdevices known heretofore.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged perspective viewof the device of the invention;

FIG. 2 is a top plan view of the device shown in FIG.

FIG. 3 is a front elevational view of the device of FIG.

FIG. 4 is a front elevational view of closure members;

FIG. 5 is a side sectional view of the device;

FIG. 6 is a side elevational view of the device showing a first closuremember inserted;

FIG. 7 is a side elevational view of the device showing first and secondclosure members inserted;

FIG. 8 is a side elevational view of the device showing all threeclosure members inserted;

FIG. 9 is a front elevational view with all closure members inserted;and

FIG. 10 is a perspective view illustrating the device as normally usedin combination with an oxygen mask and tubing.

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. ll, there isshown an oxygen dilution device Ill? of the invention having a forwardend nozzle portion 12 and a rearwardly disposed gas delivery portion 22.Intermediate between these two portions is a gas metering tunnel portion26 through which an oxygen stream flows from the nozzle portion to thegas delivery portion.

Referring also to FIGS. 2 and 5, gas metering tunnel portion 26 isdefined between rods 19 and 20, which are disposed on each side of thetunnel portion, and between arcuate ribs 14, 16 and 18. Each of thearcuate ribs extend circumferentially around tunnel portion 26 and aresecured to both rods 19 and 20. It will be noted that the ribs aresubstantially parallel and lie substantially normal to the central axisof tunnel portion 26 and along which axis gas flowing between nozzleportion 12 and gas delivery portion 22 travels. Between adjacent ribsand rib 18 and the gas delivery portion are defined a plurality of portsl3, l5 and 17 through which ports atmospheric air is directed forentrainment with and dilution of oxygen flowing through tunnel portion26.

Hollow nozzle portion 12 provides a conduit through which oxygen isdirected. The size or diameter of the hollow interior of the nozzleportion is not particularly critical. However, as shown in FIG. 5,preferably before communicating with tunnel portion 26, the nozzleportion interior includes a restricted or relatively narrow passageway24. Accordingly, gas flowing through the passageway 24 and enteringtunnel portion 26 will be in the form of a high velocity stream theefi'ect of which stream, entering the significantly larger diametertunnel portion 26, causes a partial vacuum. According to the venturiprinciple, atmospheric gas in the immediate vicinity of the tunnelportion will be entrained through open ports l3, l5 and 17 to combinewith the oxygen stream and thereby dilute its concentration. Thereafter,the diluted oxygen stream travels through hollow gas delivery portion 22and exits through open end 28. With two or more ports open, the airentrainment effect may actually be described as a cascading venturiprinciple since dilution of the oxygen stream passing along the tunnelportion is carried out in successive stages from one port to the next.

Exteriorly disposed on the forward end of nozzle portion 12 are aplurality of frustoconical segments 21 for securing an oxygen supplytube. Preferably, the first end segment has'a smaller maximum diameterthan the adjacent segment so that the segments have maximum diametersincreasing from forward to rear and provide an adaptor for attachingoxygen tubing of varying sizes. However, such features are not criticaland are merely for convenience.

Hollow gas delivery portion 22 is preferably annular so that thecircumferential exterior thereof may be easily fitted into a circularreceiving orifice of an oxygen mask or large bore tubing end fordelivery of oxygen. A flange 25 is preferably located around the outergas delivery portion surface to act as as a stop for limiting the extentto which the device extends within tubing or mask opening or orifice.Other equivalent means may be used for that purpose. However, it shouldalso be appreciated that the exterior shape as well as the hollowinterior of gas delivery portion 22 is not particularly critical so longas it can be received and secured with an oxygen mask or tubing to forma substantially gas tight seal at the receiving orifice as will beappreciated by those skilled in the art.

Observing also FIG. 4, a plurality of air restricting closure members32, 34 and 36 are used for closing gas entrainment ports 13, and 17(FIG. 2) in order to achieve varying oxygen concentrations as required.The closure members are preferably in the shape of a disc correspondingto the arcuately shaped ribs 14, 16 and 18 but which discs have a largeror greater outside diameter so that they may be relatively easilygrasped by an operator for removal or insertion along tunnel portion 26.The center area of each of the discs is also hollow and preferably doesnot interfere or project into the interior of tunnel portion 26 to avoiddeflection of the air stream passing therealong. The disc centers arealso preferably axially aligned along the central axis extending throughtunnel portion 26. The air restriction discs also are each provided witha slot 38a, 38b and 380 through which one of the rods 19 or 20 is guidedand the other rod received in securing the discs. Notches 41a, 41b and41c are also present in which one of the rods is received in furtherstabilizing secured discs.

ln securing a disc, it is simply placed on the device so that a discwill fill or stopper one of the ports. A disc is secured by passing rod19 through a slot (38a) and pressing the disc in place until rod 20 isreceived in slot 38a and rod 19 is received in notch 41a.

Observing also FIGS. 6, 7 and 8, it will be noted that disc 32 not onlyhas a larger hollow center than discs 34 or 36 but that the latter discsare respectively thinner. Thus, the thickness of each disc correspondsto the width of the ports in which the respective disc fits andpreferably all are different so that each disc will fit only one port.For this purpose not only may the port sizes (distance between adjacentribs) be different, but the width of rods 19 and 20 between adjacentribs as well as corresponding disc slot and notch sizes may vary. Such afeature will prevent an inexperienced operator from inadvertentlyplacing the wrong disc on the wrong port. This feature is further notedin observing FIG. 3 in which rod portions 44, 46 and 48 between adjacentribs are progressively smaller in both length and width.Correspondingly, observing FIG. 5, the distance across slots 38a, 38band 380 and notches 41a, 41b and 410 are progressively smaller.

It should be appreciated that the device may have a different shape asmay the closure members. For exampie, rather than the ribs and rodsfonning a generally frustoconical outline, ribs may be formed withsimilar modification of the closure member shape in rectangular, square,or other forms. Moreover, the discs may be color coded to furtherdistinguish them. Such modifications will be evident to those skilled inthe art without departing from the purview of the invention.

In operation, the device is utilized and functions as follows:

Observing FIG. 10, oxygen supply tubing 44 is secured to nozzle portion12 and gas delivery portion 22 is inserted and received in the end ofoxygen delivery tube 46. The delivery tubing is connected to oxygen mask45 which is secured to a patient as shown. Alternatively, the device maybe secured directly to an oxygen mask thereby eliminating deliverytubing if desired. The operator or therapist then selects the desiredoxygen concentration to be delivered to the patient, for example, 24percent, 28 percent, 35 percent or 40 percent. Where 24 percent oxygenis to be delivered to the patient, none of the discs are inserted on thedevice so that all three of gas entraining ports 13, 15 and 17 are openas shown in FIGS. 1, 2 and 5. Accordingly, at an oxygen flow rate of forexample, 4 liters per minute the air entrained through the ports providean oxygenatmospheric air mixture of about 24 percent oxygenconcentration delivered to the patient. For a 28 percent oxygenconcentration, disc 32 is inserted as shown in FIG. 6 closingappropriate oxygen entraining port. At the same flow of 4 liters perminute through the oxygen supply tubing an oxygen concentration of 28percent delivered to the patient will be achieved. For 35 percent oxygenconcentration, two of the restriction discs are secured as shown in FIG.7 and in order to increase total flow to the patient, oxygen flow isincreased, for example, to eight liters per minute. With a third discinserted to close all of the air entraining ports as shown in FIG. 8, 40percent oxygen concentration will be delivered to a patient.

Observing also FIG. 9, it will be noted that disc 36 has an oblonghollow center so that there is a vent opening 35 adjacent nozzle portion12. Thus, even all closure members secured some air will be entrainedthrough the vent in order to avoid delivery of unduly high oxygenconcentrations. The size of such a vent opening of course, may be variedto achieve any maximum oxygen concentration desired.

Again, the shape of the ribs of the device of the invention is notparticularly critical and rather than being arcuate, they may berectangular, square or some other shape, so long as the air entrainingtunnel portion is not adversely affected. Further, the port sizes andshapes may be varied as well as the number of ports incorporated in sucha device to achieve a series of different oxygen concentrations as willbe appreciated by those skilled in the art. Although the closure membersare shown as slotted and notched so that they may be easily fitted overand secured on the rods which extend between the forward-most rib andthe forward end of gas delivery portion 22, other design characteristicswhich achieve the same purpose are' intended to be within the purview ofthe invention.

It will be appreciated that the device of the invention provides varyingoxygen concentrations on a single unit without the requirement of havingdifferent devices for each different oxygen concentration desired ashave the corresponding prior art devices. Accordingly, a single deviceof the invention can be used on a single patient whereby varying oxygenconcentrations may be selected by simply inserting or removing one ormore of the closure members when the unit is to be used as previuslydescribed. These as well as other advantages will be evident to thoseskilled in the art.

1 claim:

1. A device for diluting an oxygen stream delivered to a patientcomprising:

a. a nozzle portion disposed at one end for attaching an oxygen supplytube;

b. a hollow gas delivery portion at the opposite end for directing gasto the patient;

c. a hollow tunnel portion extending between the nozzle and gas deliveryportions including a pair of oppositely disposed rods extending betweensaid nozzle and gas delivery portions and a plurality of arcuate andparallel ribs secured around both sides of said rods and spacedtherealong whereby a tunnel is defined interiorly of said ribs and rodsand a plurality of ports are defined between said ribs; and

d. a closure member for each port for being selectively secured on saiddevice to close at least a portion of a respective port whereby anoxygen stream flowing through the tunnel portion is mixed and dilutedwith entrained air entering through one or more open ports.

2. The device of claim 1 wherein said closure members comprise airrestriction discs each of which is shaped to substantially occlude oneof said ports.

3. The device of claim 1 wherein said nozzle portion includes arestricted passageway for creating a high velocity oxygen streamdirected into said tunnel portion.

4. The device of claim 3 wherein said device has three of said ports andclosure members and wherein with all three of said closure memberssecured an oxygen concentration of about 40 percent is delivered at aflow rate of 8 liters per minute, with two of said closure memberssecured an oxygen concentration of about 35 percent is delivered at 8liters per minute flow, with one of said closure members secured anoxygen concentration of about 28 percent is delivered at 4 liters perminute flow, and with no closure members secured and all ports open anoxygen concentration of about 24 percent is delivered at 4 liters perminute flow.

1. A device for diluting an oxygen stream delivered to a patientcomprising: a. a nozzle portion disposed at one end for attaching anoxygen supply tube; b. a hollow gas delivery portion at the opposite endfor directing gas to the patient; c. a hollow tunnel portion extendingbetween the nozzle and gas delivery portions including a pair ofoppositEly disposed rods extending between said nozzle and gas deliveryportions and a plurality of arcuate and parallel ribs secured aroundboth sides of said rods and spaced therealong whereby a tunnel isdefined interiorly of said ribs and rods and a plurality of ports aredefined between said ribs; and d. a closure member for each port forbeing selectively secured on said device to close at least a portion ofa respective port whereby an oxygen stream flowing through the tunnelportion is mixed and diluted with entrained air entering through one ormore open ports.
 2. The device of claim 1 wherein said closure memberscomprise air restriction discs each of which is shaped to substantiallyocclude one of said ports.
 3. The device of claim 1 wherein said nozzleportion includes a restricted passageway for creating a high velocityoxygen stream directed into said tunnel portion.
 4. The device of claim3 wherein said device has three of said ports and closure members andwherein with all three of said closure members secured an oxygenconcentration of about 40 percent is delivered at a flow rate of 8liters per minute, with two of said closure members secured an oxygenconcentration of about 35 percent is delivered at 8 liters per minuteflow, with one of said closure members secured an oxygen concentrationof about 28 percent is delivered at 4 liters per minute flow, and withno closure members secured and all ports open an oxygen concentration ofabout 24 percent is delivered at 4 liters per minute flow.